 The Gamber–Finksburg portion of MD 91 was originally a turnpike called the Mechanicsville and Finksburg Turnpike, which later became one of the branches of the Baltimore and Reisterstown Turnpike.The first section of modern road built along the highway was a macadam road from the Western Maryland Railway (now Maryland Midland Railway) south to near Beaver Run.A concrete road was laid in two segments from Gamber toward Finksburg in 1923 and 1924.